Investments - BeOne (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Net Investment Income [Line Items]
Equity securities	$ 6,144	$ 4,188
Unrealized gain (loss) on equity method investment	109	(21)	$ 98
BeOne
Net Investment Income [Line Items]
Unrealized gain (loss) on equity method investment	2,300	82	1,200
Other Noncurrent Assets
Net Investment Income [Line Items]
Equity securities	326	314
Neumora Therapeutics, Inc.
Net Investment Income [Line Items]
Equity securities	63	375
Unrealized gain (loss) on equity method investment	$ (312)	$ (228)	$ 238
BeOne
Net Investment Income [Line Items]
Ownership percentage	17.10%	17.80%
BeOne \| Maximum
Net Investment Income [Line Items]
Ownership percentage	5.00%	5.00%
BeOne \| Other Noncurrent Assets \| BeOne
Net Investment Income [Line Items]
Equity securities	$ 5,800	$ 3,500

Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 10
-Topic 321
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482736/825-10-45-1A

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-4

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